All right, we get right to texas now. Parts of the state are under emergency warning because of a massive outbreak of west nile virus. Dallas county, in fact, unleashing what you see here. An aerial attack of insecticide overnight to combat the insect population there. Over two dozen cases of the disease. And ten deaths. Ryan owens has the very latest. Good morning to you, ryan. Reporter: Good morning to you, josh. That aerial spraying went on into the wee hours of the morning. People here warned to stay inside. County officials say it was a big success. But not without a lot of controversy. After all, this is the first time dallas has been sprayed like this in almost 50 years. Moments ago, planes began taking off -- traveling at 172 miles per hour. Reporter: The overnight aerial attack was carried live on the local news. Aerial spraying to fight west nile virus under way at this hour. Reporter: Two, small planes flying just a few hundred feet above neighborhoods, raining pesticide down on one of america's biggest cities. Dallas' mayor hoped it wouldn't come to this. When you're dealing with people's lives, that should come first and foremost. Reporter: The planes are the latest weapons in the war on mosquitos. Crews have been spraying on the ground for several weeks now. But the death toll keeps climbing. Ten have now died. So, now, the aerial assault. The e.P.A. Says the chemical mist is only harmful to people or pets if it's swallowed. But some doctors disagree, saying people with asthma or respiratory problems are at risk. I'm telling them if they're sensitive to leave town. Reporter: The pesticide is toxic to bees and fish. That's why homeowners scrambled to cover their backyard gardens and ponds. Katharyn is one sickened in dallas county. From her hospital bed, she is happy to those planes in the air. I don't want anybody to get this. If it means they go and spray from the air, do it. Reporter: Opponents of spraying will not be happy to hear this. More is scheduled tonight and into next week. Actually, two more planes are headed to dallas to do this. Officials, amy, are hoping this will finally do what nothing else has. And that is to slow the spread of this virus. All right. Ryan owens, thanks for that.

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